p ART I.—THE DESCENT OF MAN. 



CHAPTEK I. 



The Evidence of the Descent of Man from some 



Lower Form. 



Nature of the evidence bearing on the origin of man — Homologous 

 structures in man and the lower animals — Miscellaneous points 

 of correspondence — Development — Rudimentary structures, 

 muscles, sense-organs, hair, bones, reproductive organs, &c. — 

 The bearing of these three great classes of facts on the origin 

 of man. 



He who wishes to decide whether man is the modified 

 descendant of some pre-existing form, would probably 

 first enquire whether man varies, however slightly, in 

 bodily structure and in mental faculties; and if so, 

 whether the variations are transmitted to his offspring 

 in accordance with the laws which prevail with the lower 

 animals; such as that of the transmission of characters 

 to the same age or sex. Again, are the variations the re- 

 sult, as far as our ignorance permits us to judge, of the 

 same general causes, and are they governed by the same 

 general laws, as in the case of other organisms ; for in- 

 stance by correlation, the inherited effects of use and 

 disuse, &c. ? Is man subject to similar malconformations, 

 the result of arrested development, "of reduplication of 

 parts, &o, and does he display in any of his anomalies 

 reversion to some former and ancient type of structure ? 

 It might also naturally be enquired whether man, like 

 so many other animals, has given rise to varieties and 

 sub-races, differing but slightly from each other, or to 



